1. Field of the Invention
The present invention generally relates to sliding doors. More specifically, the present invention relates to automatic sliding door closure devices.
2. Description of the Prior Art
Many buildings and homes have manually or automatically operated sliding doors. Many of the sliding doors used in commercial settings are designed with elaborate systems to automatically open when approached and close after a period of time. The following are previously issued United States Patents disclosing sliding door closure systems of this type.
U.S. Pat. No. 4,357,732 issued to Hickman discloses an automatic door closer kit for a sliding door assembly. The door closure kit is gravity actuated and comprises a counterbalance having an adjustable weight capacity, an anchor pulley mechanism having a grooved pulley wheel thereon and mounted on the lintel and one of the rails, a traveling pulley mechanism having a grooved pulley wheel thereon and mounted on the upper edge of the second side of a movable door, and a lifting pulley mechanism having a grooved pulley wheel thereon and mounted on an upper portion of the stationary panel adjacent a second frame. A cord, having one end attached to the counterbalance, is entrained over the lifting pulley then about the anchor pulley and about the traveling pulley and the other end is secured to a hook on the anchor pulley mechanism.
U.S. Pat. No. 5,131,188 issued to Hutchison discloses a device for automatically returning a sliding door or window to a predetermined position within a stationary frame.
The sliding doors used in most households are typically designed to be manually opened and closed. Several different types of kits have been devised to retrofit a manually operated door to automatically close these types of doors. The following are previously issued United States Patents disclosing sliding door closure devices of this type.
U.S. Pat. No. 4,097,957 issued to Kitutka discloses an automatic door closing device for use in a sliding type door. The device includes a driving section having a spiral spring disposed in a casket to urge the sliding door toward closing direction and a buffer mechanism having a cylinder and a piston for moderating closing speed of the door. The device is sufficient for its intended use but requires lubricating oil to operate, making the maintenance of the device messy.
U.S. Pat. No. 5,622,007 issued to Archer discloses an automatic sliding door closing device comprised of two elongated arms coupled together at their proximal ends by a coiled spring which spreads the distal ends of the elongated arms apart. This type of device is simpler in design but presents an unattractive appearance when in use.
Accordingly, there is a need for an automatic door closure device that may be easily installed on a preexisting sliding door in household settings that does not require lubrication oil for operation, and is not obtrusive to the aesthetic appearance of the sliding door entry.